Golf club head having a brazed striking plate

ABSTRACT

A golf club head includes a casing with a front open end to which a striking plate is attached through a layer of brazing material that is formed between a rear surface of the striking plate and a frontmost end face of the casing. One of the striking plate and the front open end of the casing has an extension part which projects outward in a direction away from the opening. The extension part forms a shoulder with one of the first and second outer peripheral faces. During a brazing process, the brazing material is positioned against the shoulder externally of a clearance between the rear surface and the frontmost end face and is then melted to flow into the clearance through a capillary action.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a golf club head, more particularly to a golfclub head which has a casing and a striking plate brazed to an open endof the casing.

2. Description of the Related Art

As more and more people like playing golf, either for pleasure or forphysical exercise, the prior art have suggested various types of golfclubs to meet the increasing demand therefor. FIG. 1 shows a golf clubhead which includes a casing 10 and a striking panel 11. The casing 10has an opening 12 covered by the striking panel 11 which is slightlygreater than the opening. A rib 13 projects forwardly from an edge ofthe casing 10 which confines the opening 12 and extends around theopening 12 to engage a groove 14 which is formed in a rear surface ofthe striking panel 11 along the periphery of the striking panel 11. Awelding layer 15 is provided between the surfaces of the striking panel11 and the casing 10. The welding layer 15 is formed between the jointsurfaces of the casing 10 and the striking panel 11 by melting a brazingmaterial between the joint surfaces. The striking panel 11 and thecasing 10 are coupled together after the brazing material is cooled.

Although the interengagement of the rib 13 and the groove 14 canincrease the contact surface areas between the casing 10 and thestriking panel 11, as the brazing material is pre-arranged only at theedge of the opening 12 of the casing 10, the amount thereof is limitedby the length of the edge of the opening 12. If the amount of thebrazing material is insufficient, the bonding effect of the weldinglayer 15 between the casing 10 and the striking panel 11 will bereduced.

During fabrication, the brazing material is placed along the edge of theopening 12 of the casing 10 before the striking panel 11 is attached tothe casing 10. When the striking panel 11 is attached to the casing 10to cause the groove 14 to engage the rib 13, the brazing material issqueezed between the groove 14 and the rib 13. When the brazing materialis melted by heat, it oozes outward from the clearance between thegroove 14 and the rib 13 and is solidified at the outer surfaces of thestriking panel 11 and the casing 10. In order to remove the brazingmaterial solidified at the outer surfaces, the striking panel 11 and thecasing 10 must be subjected to manual or mechanical surface treatingprocesses, such as grinding and/or polishing. The manufacturing processas such is laborious and time-consuming due to the need for surfacetreatment.

FIG. 2 shows another conventional golf club head which includes a metalcasing 20 and a striking panel 21 as shown in FIG. 2. The casing 20 isformed with a recess 22 and a shoulder 23 to seat the striking panel 21thereon, and the striking panel 21 is formed with a groove 24 at anouter edge thereof to engage a rib 25 formed on an inner surface of thecasing 20 and extending around the opening thereof. The rib 25 is formedby softening and deforming a portion of the casing 20 adjacent theopening of the casing 20. The striking panel 21 is fixed to the casing20 by brazing. This conventional golf club head also encounters aproblem in that the brazing material oozes out and stains the outersurfaces of the casing 20 and the striking panel 21 during manufacture.

On the other hand, while the interlocking of the rib 25 and the groove24 increases the firmness of the joint between the striking panel 21 andthe casing 20, it is required that the rib 25 be formed at an accurateposition so as to precisely mate with the groove 24 of the strikingpanel 21. Since the rib 25 is formed by heating and deforming a portionof the casing 20 proximate to the position of the groove 24 after thestriking panel 21 is attached to the casing 20, once the striking panel21 is attached, the groove 24 is covered by the casing 20 so that it isdifficult to determine the exact position of the groove 24. Therefore,difficulties are encountered in processing the casing 20 to form the rib25 at an accurate position relative to the groove 24. Unless the casing20 is provided with a mark or measurement to indicate the position wherethe rib 25 is to be provided, it is impossible to form the rib 25 at anaccurate position that permits the rib 25 to mate precisely with thegroove 24.

Referring to FIG. 3, in a conventional method for coupling a golf clubhead casing and a striking plate, before the striking plate 30 is placedin a recess 32 of a casing 31, a brazing material 34 is put on ashoulder face 33 formed at the recess 32. Thereafter, the striking plate30 is inserted into the recess 32 so that the brazing material 34 ispressed between the striking plate 30 and the shoulder face 33. When thestriking plate 30 and the casing 31 are heated under vacuum, the brazingmaterial 34 melts and fills the space between the casing 31 and thestriking plate 30, thereby welding the striking plate 30 to the casing31.

In the aforesaid method, the casing 31, the striking plate 30 and thebrazing material 34 have different melting points, and the brazingmaterial 34 which has the lowest melting point is melted to interconnectthe casing 31 and the striking plate 30. However, since the brazingmaterial 34 is in a powder form, when the brazing material 34 melts, thevolume thereof contracts so that the brazing material 34 cannot fill theclearance between the joint surfaces of the casing 31 and the strikingplate 30 completely. This results in voids between the joint surfaces ofthe striking plate 30 and the casing 31, thereby reducing the bindingstrength therebetween, and adversely affecting the stability of the golfclub head.

In order to address the aforesaid problem arising from the contractionof the brazing material, an attempt has been made by increasing theamount of the brazing material 34. However, when the amount of thebrazing material 34 is increased, the thickness of the brazing material34 between the surfaces of the casing 31 and the striking plate 30 isincreased, thereby enlarging the distance between the joint surfaces ofthe casing 31 and the striking plate 30. Therefore, if the amount of thebrazing material 34 is increased too much, the binding strength can alsobe reduced. In addition, the brazing material can be wasted. It is adifficult task to balance the amount of the brazing material and thebinding strength.

Furthermore, after the striking plate 30 is placed in the recess 32 andis pressed against the brazing material 34 which has been placed on theshoulder face 33 within the recess 32, even if voids are formed betweenthe shoulder surface 33 and the striking plate 30 because of theinsufficient amount of the brazing material 34, it is impossible to addthe brazing material 34 to the voids by removing the striking plate 30from the casing 31. In addition, during the manufacturing process, it isnot easy to realize the presence of such voids in the products.Therefore, the aforesaid method cannot be relied upon to produce goodquality products.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a golf club head with aconstruction in which a brazing material can be introduced easilybetween the surfaces of a striking plate and a casing of the golf clubhead without staining the outer surfaces of the casing and the strikingplate.

According to this invention, a golf club head comprises: a casing havinga front open end defining an opening, the front open end having afrontmost end face and a first outer peripheral face extendingrearwardly from the frontmost end face; a striking plate attached to thefront open end to cover the opening and including a rear surfaceconfronting the frontmost end face, a front surface opposite to the rearsurface, and a second outer peripheral face that extends forwardly fromthe rear surface to the front surface; and a layer of brazing materialbonding the rear surface to the frontmost end face and formed within aclearance between the rear surface and the frontmost end face, one ofthe striking plate and the front open end having an extension part whichprojects outward in a direction away from the opening and along a planeof the layer of brazing material, the extension part forming a shoulderwith one of the first and second outer peripheral faces, the shoulderbeing exterior to and immediately adjacent to the clearance, whereby theshoulder is adapted to hold the brazing material during a brazingprocess.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features and advantages of the present invention will becomeapparent in the following detailed description of the preferredembodiments of the invention, with reference to the accompanyingdrawings, in which:

FIG. 1 is a sectional view of a conventional golf club head;

FIG. 2 is a sectional view of another conventional golf club head;

FIG. 3 is a sectional view of still another conventional golf club head;

FIG. 4 is a sectional view of a golf club head embodying the presentinvention;

FIG. 5 is a front view of the golf club head of FIG. 4;

FIG. 6 is a block diagram illustrating a first preferred embodiment ofthe method according to the present invention;

FIG. 7 is a sectional view illustrating how a brazing material ispositioned in the first preferred embodiment;

FIG. 8 is a sectional view illustrating how a brazing material ispositioned in a second preferred embodiment of the method according tothe present invention;

FIG. 9 is a sectional view of a golf club head produced by the method ofthe second embodiment;

FIG. 10 is a front view of the golf club head shown in FIG. 9;

FIG. 11 is a sectional view illustrating how the brazing material ispositioned in a third preferred embodiment of the method according tothe present invention;

FIG. 12 is a front view of the golf club head produced by the thirdembodiment;

FIG. 13 is a sectional view illustrating how the brazing material ispositioned in a fourth preferred embodiment of the method according tothe present invention;

FIG. 14 is a front view of the golf club head produced by the fourthembodiment;

FIG. 15 is a sectional view of another golf club head produced by thefirst preferred embodiment;

FIG. 16 is a sectional view of another golf club head produced by thesecond preferred embodiment;

FIG. 17 is a sectional view of another golf club head produced by thethird preferred embodiment; and

FIG. 18 is a sectional view of another golf club head produced by thefourth preferred embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Before the present invention is described in greater detail, it shouldbe noted that same reference numerals have been used to denote likeelements throughout the specification.

Referring to FIGS. 4 and 5, a golf club head embodying the presentinvention is shown at 4 and includes a metal casing 41 and a strikingplate 42 which are brazed to each other. A layer of brazing material 43is formed between the welded surfaces of the casing 41 and the strikingplate 42. The casing 41, the striking plate 42 and the brazing material43 are made of different metals, and the melting point of the brazingmaterial 43 is lower than those of the casing 41 and the striking plate42.

The casing 41 has a front open end 412 which defines an opening 411. Thefront open end 412 has a frontmost end face 413 and a first outerperipheral face 414 extending rearwardly from the frontmost end face413.

The striking plate 42 has a front surface 420, a rear surface 422, and asecond outer peripheral face 423 which extends forwardly from the rearsurface 422 to the front surface 420. The striking plate 42 covers theopening 411 of the casing 41, and the rear surface 422 is placed overthe frontmost end face 413 of the casing 41. The rear surface 422interlocks with the frontmost end face 413 of the casing 41 throughinterlocking elements provided therebetween. In this embodiment, theinterlocking elements include a projection 415 which projects forwardlyfrom the frontmost end face 413 and a groove 421 formed in the rearsurface 422. The layer of brazing material 43 is formed between the rearsurface 422 of the striking plate 42 and the frontmost end face 413 ofthe casing 41.

The striking plate 42 further has a plurality of extension parts 40which project outward in a direction away from the opening 411 and alongthe plane of the layer of brazing material 43. Each extension part 40extends beyond the first outer peripheral face 414 of the casing 41 andforms a shoulder 400 with the first outer peripheral face 414.

Referring to FIGS. 6 and 7, a first preferred embodiment of the methodaccording to the present invention is illustrated as including apreparation step 51, an assembling step 52, a brazing materialpositioning step 53, and a brazing step 54. The first preferredembodiment is conducted to produce the golf club head 4.

The preparation step 51 includes the forming of the casing 41, thestriking plate 42, and a plurality of pieces of the brazing materials43.

In the assembling step 52, the casing 41 and the striking plate 42 arebrought together by contacting the rear surface 422 of the strikingplate 42 with the frontmost end face 413 of the casing 41 and byengaging the projection 415 of the frontmost end face 413 with thegroove 421 of the striking plate 42. A clearance is formed between therear surface 422 and the frontmost end face 413. Shoulders 400 areformed around the first outer peripheral face 414. The shoulders 400 areexterior to and are connected to the clearance between the rear surface422 and the frontmost end face 413.

In the brazing material positioning step 53, pieces of the brazingmaterial 43 are seated respectively against the shoulders 400 which areparts of the rear surface 422 of the striking plate 42. The brazingmaterial 43 is therefore positioned outwardly of the opening 411 andexternally of the clearance between the rear surface 422 and thefrontmost end face 413 and is immediately adjacent the clearance.

In the brazing process 54, the casing 41 and the striking plate 42 whichhave been brought together are placed in a high temperature environment.The high temperature environment may be an oven which is provided with avacuum pressure or filled with an inert gas. In this embodiment, avacuumed oven is used. Since the melting point of the brazing material43 is lower than the melting points of the casing 41 and the strikingplate 42, only the brazing material 43 melts in the oven. The melt ofthe brazing material 43 flows from the shoulder 400 into the clearancebetween the rear surface 422 and the frontmost end face 413 through acapillary action. When the brazing material 43 is cooled, it is bondedto the rear surface 422 and the frontmost end face 413, therebyinterconnecting the striking plate 42 and the casing 41.

Referring to FIGS. 8, 9 and 10 in combination with FIG. 6, a secondpreferred embodiment of the method according to the present invention isused to produce a golf club head 4A. This embodiment is generallysimilar to the first preferred embodiment. However, in this embodiment,extension parts 40A are formed integrally with the casing 41, unlike theextension part 40 provided in the first embodiment. Each extension part40A extends outwardly from the front open end 412 of the casing 41 in adirection away from the opening 411 and forms a shoulder 400A with thesecond outer peripheral face 423 of the striking plate 42. The shoulder400A is a part of the frontmost end face 413 of the casing 41. Duringthe step of positioning the brazing material 43, the brazing material 43is seated against the shoulder 400A as shown in FIG. 8. As the shoulder400A are formed outwardly of the opening 411, the brazing material ispositioned at the outer side of the opening 411 and at the exterior ofthe clearance between the rear surface 422 and the frontmost end face413 during the manufacturing process. Furthermore, the projection 415formed on the front open end 412 of the casing 41 is provided with aslanting face 416 and the groove 421 is provided with a slanting face426 so as to increase the areas of the contact surfaces of the strikingplate 41 and the front open end 412 of the casing 41.

Due to the provision of the shoulders 400, 400A which are formedoutwardly of the opening 411 of the casing 41, the brazing material 43can be positioned easily and accurately on the shoulders 400, 400Aduring the manufacturing of the golf club head 4, 4A. In addition, sincethe brazing material 43 is positioned on the shoulders 400, 400A ratherthan between the striking plate 42 and the front open end 412 of thecasing 41, positional deviation occurring during the manufacturingprocess can be prevented and the rate of good quality products can beincreased.

Besides, the increased contact surface areas of the striking plate 42and the casing 41 provide more surface area to which the brazingmaterial 43 can be adhered, thereby increasing the bonding surface areabetween the striking plate 42 and the casing 41.

On the other hand, since the brazing material 43 is introduced into theclearance between the striking plate 42 and the casing 41 through acapillary action in the present invention and since the clearancepermits only a small amount of brazing material 43 to flow thereinto,the brazing material 43 forms only a thin film layer between thestriking plate 42 and the casing 41, thus providing stable and firmbonding between the striking plate 42 and the casing 41.

Furthermore, as the brazing material flows into the clearance betweenthe striking plate 42 and the casing 41 from the outside of theclearance, the problem associated with the conventional manufacturingmethod in which the brazing material overflows to the exterior surfaceof the golf club head can be eliminated. According to the presentinvention, the amount of the brazing material 43 which is suitable forbonding the striking plate 42 and the casing 41 may be predetermined sothat the brazing material 43 not only is sufficient to bind the strikingplate 42 and the casing 41 but also leaves only a small amount ofresidue on the shoulder 400, 400A. As such, subsequent processing steps,such as grinding and polishing steps, for removal of the residue can bedispensed with.

Moreover, if there are voids between the contact surfaces of the casing41 and the striking plate 42, the brazing material 43 may besupplemented by placing an additional amount of the brazing material 43on the shoulders 400, 400A followed by heating so that the brazingmaterial 43 flows into the voids. Therefore, the present inventionenhances the rate of quality products and is advantageous in solving theproblem of poor bonding between the striking plate 42 and the casing 41due to the insufficient amount of brazing material 43.

FIGS. 11 and 12 show a golf club head 4B to be coupled with a woodenshaft which is made by a third preferred embodiment of the methodaccording to the present invention. The golf club head 4B has extensionparts 40B extending outwardly from the striking plate 42B in a directionaway from the opening 411B of the casing 411B. The extension parts 40Bform shoulders 400B with an outer peripheral face 414B of the casing411B. In this embodiment, the brazing material 43 is seated against theshoulders 400B.

FIGS. 13 and 14 show a golf club head 4C to be coupled with a woodenshaft which is made by a fourth preferred embodiment of the methodaccording to the present invention. The golf club head 4C has extensionparts 40C extending outwardly from the front open end 412B in adirection away from the opening 411B of the casing 41B. The extensionparts 40C form shoulders 400C with the casing 41B. In this embodiment,the brazing material 43 is seated against the shoulders 400C.

FIG. 15 shows another golf club head 4D which is made by the firstembodiment of the method of the present invention. The golf club head 4Ddiffers from the golf club head 4 shown in FIG. 4 only in that noprojection and groove are provided on the rear surface 422 of thestriking plate 42 and the frontmost end face 413 of the casing 41.

FIG. 16 shows another golf club head 4E which is made by the method ofthe second preferred embodiment. The golf club head 4E differs from thegolf club head 4A shown in FIG. 9 only in that no projection and grooveare provided on the rear surface 422 of the striking plate 42 and thefrontmost end face 413 of the casing 41.

FIG. 17 shows another golf club head 4F which is made by the method ofthe third preferred embodiment. The golf club head 4F differs from thegolf club head 4B shown in FIG. 11 only in that no projection and grooveare provided on the rear surface 422 of the striking plate 42 and thefrontmost end face 413 of the casing 41.

FIG. 18 shows another golf club head 4G which is made by the method ofthe fourth preferred embodiment. The golf club head 4G differs from thegolf club head 4C shown in FIG. 13 only in that no projection and grooveare provided on the rear surface 422 of the striking plate 42 and thefrontmost end face 413 of the casing 41.

While the present invention has been described in connection with whatis considered the most practical and preferred embodiments, it isunderstood that this invention is not limited to the disclosedembodiments but is intended to cover various arrangements includedwithin the spirit and scope of the broadest interpretations andequivalent arrangements.

1. A golf club head comprising: a casing having a front open enddefining an opening, said front open end having a frontmost end face anda first outer peripheral face extending rearwardly from said frontmostend face; a striking plate attached to said front open end to cover saidopening and including a rear surface confronting said frontmost endface, a front surface opposite to said rear surface, and a second outerperipheral face that extends forwardly from said rear surface to saidfront surface; and a layer of brazing material bonding said rear surfaceto said frontmost end face and formed within a clearance between saidrear surface and said frontmost end face, one of said striking plate andsaid front open end having an extension part which projects outward in adirection away from said opening and along a plane of said layer ofbrazing material, said extension part forming a shoulder with one ofsaid first and second outer peripheral faces, said shoulder beingexterior to and immediately adjacent to said clearance, whereby saidshoulder is adapted to hold said brazing material during a brazingprocess.
 2. The golf club head as claimed in claim 1, wherein saidstriking plate has said extension part, said extension part forming saidshoulder with said first outer peripheral face.
 3. The golf club head asclaimed in claim 1, wherein said front open end of said casing has saidextension part, said extension part forming said shoulder with saidsecond outer peripheral face.
 4. The golf club head as claimed in claim1, wherein said rear surface and said frontmost end face are providedwith interlocking elements which interlock said rear surface and saidfrontmost end face.
 5. The golf club head as claimed in claim 4, whereinsaid interlocking elements include a projection formed on one of saidrear surface and said frontmost end face, and a groove formed on theother one of said rear surface and said frontmost end face to engagesaid projection.
 6. The golf club head as claimed in claim 5, whereinsaid projection has a slanting face, said groove having a slanting faceengaging said slanting face of said projection.